Well I broke my AFX140 modular yesterday morning. I left it in the garage Wednesday night (26 degrees f) for some reason, usually I bring it inside the house with me. I went to put it on yesterday morning and snapped the plastic trim pieces along the botom edge of the helmet. I was wearing a neck warmer so I've been spreading the bottom of the helmet to get it on over that, I've put it on 100 times the very same way before but this time the helmet was 26f and the plastic was super brittle.
The AFX was my winter helmet because the anti-fog shield actually works and it does a much better job of not fogging then my HJC CL-MaxII does.
It's been a bad helmet year for me, I dropped my Bell earlier this year and it landed right on one of the vents and broke it off so I replaced it with the AFX, now I break the AFX putting it on (it's probably not even 6 months old). I couldn't bring myself to buy another one this year so the HJC will be my new winter helmet. I can't put up with the fogging though so I did buy myself a Xmas present, I just installed a pinlock shield. Rather expensive ($58 for shield and insert) but it was cheaper than a new helmet.
If your helmet has any plastic parts, do yourself a favor and keep it warm.
Makes you wonder what would happen if you hit the pavement while riding to work.
I know, I thought the same thing. I'm sure the plastic parts are very brittle on my way to and from work at that temp.
The only comforting thing is that I would consider the plastic trim pieces to be non structural, I don't think the integrety of the helmet is compromised much if any but I would definately have plastic pieces flying everywhere if I were to hit the pavement hard.
I've replaced plastic parts on my Arai on two separate occasions. They break at pretty much any temperature if you drop your helmet on a hard surface. They supply the parts free of charge. Other brands such as Scorpion, HJC, Bell, etc. supply the parts but may charge a nominal amount for them. No need to replace a helmet just because of a broken plastic vent or other minor issue, these are easily replaceable. Dropping an empty helmet from just a few feet is not going to compromise it's integrity. In most cases you will need to contact the warranty service provider directly rather than the store though to buy parts.
My goal is to live forever, so far so good.